Many people are sufficiently physically impaired that they are unable to use their legs or have very limited or unbalanced use of their legs, and are thus conventionally restricted to self-powered mobility in the form of a wheel chair or stiff leg braces used with a walking frame which nearly surrounds the user.
These conventional limitations of mobility have been overcome to a large degree by a cable-based orthopedic appliance often referred to as a reciprocating gait orthosis or brace, such as the device sold under the proprietary name of "LSU Reciprocating Gait Orthosis" by Durr-Fillauer Medical, Inc. of Chattanooga, Tenn. This device uses right and left hip joint assemblies. Each hip joint assembly includes a lower hip joint bar which rotates relative to an upper hip joint bar. The upper bar is fixed in position relative to the side of the torso of the user. The lower bar is fixed in position relative to the outer side of the upper leg of the user, forming a hip joint where the two bars are pivotally attached. Hip joint assembly on each side, in effect, has protrusions which extend anteriorly and posteriorly of the pivot connection. A cable connects the two anteriorly extending protrusions and a second cable connects the two posteriorly extending protrusions. These cables extend slidably in sheathes that are fixed in position to the upper bars.
One way to change the relative rotational positions of the upper and lower bars is by replacing the cables with cables of different lengths. This is desirable where the individual is not able to stand fully upright due to the shortening of muscles in the front of the hip.
Further, the anteriorly extending protrusions on the lower bars cause bulges in the clothing of the user and prevent the natural spreading of the hips when the user assumes a sitting position. The cable travelling through the sheath provides resistance to leg movement in the form of friction. This friction causes heating and wearing of the sheath wastes energy and tires the patient. The range of hip motion may be limited by an insufficient length of bare cable between the sheath end and the cable attachment at the hip joint assembly. The cable linkage typically has some free play which allows the lower hip joint bars to move a little without transferring force between them.
It is also desirable to have a hip reciprocating apparatus which takes up less space, operates simply, is less expensive to make, and is lighter in weight.
The present invention provides a hip reciprocating apparatus which overcomes these disadvantages of the prior art. In particular, it provides such an apparatus which minimizes friction, improves cosmesis, and is simple in design, structure and operation.
Generally, the present invention provides an apparatus positionable adjacent the hips of a human body for facilitating walking. Included is a base member, also referred to as a reciprocating gait brace, positionable adjacent the hips of a human body and extending from one hip to the other hip when positioned for use. A pivot member has an end extending adjacent each hip and is attached to the base member for pivoting relative to the base member in a manner whereby the pivot member ends move vertically in opposite directions with pivoting of the pivot member. A leg member is attached to the base member adjacent each hip and extends along the human leg for pivoting relative to the base member about an axis extending laterally of the base member. Finally, a linkage couples each pivot member end with the associated leg member for pivoting the two leg members when the pivot member pivots relative to the base member.
In a preferred embodiment of the present invention, the base member, positionable adjacent the hips of a human body, has a back extending from one hip, behind the torso of the body, to the other hip when positioned for use. The pivot member is elongate in a C-shape, extends across the back of the base member between ends that are adjacent each hip, and is attached at a central location to back of the base member. The pivot member pivots about a generally horizontal axis relative to the base member in a manner whereby the pivot member ends move vertically in opposite directions with pivoting of the pivot member.
Each leg member pivots relative to the base member about an axis extending laterally of the base member. The linkage is adjustable in length and is attached to the leg member posteriorly of the pivot axis between the leg member and base member.
It can be seen that such a device provides many advantages over the prior art. The pivot arm transfers force from one leg to the other by a simple mechanically direct means which fits into the small of the user's back, has only the minimal friction of pivot joint, provides an extended range of hip motion, and has reduced manufacturing costs and other advantages.
These and other features and advantages of the present invention will be apparent from the following detailed description and the accompanying drawings.